JavaScript: how to paginate an array

In this article we'll see how to paginate an array with JavaScript.

We can implement the following solution:

'use strict';

function paginateArray(arr = [], pageSize = 1, pageNumber = 1) {
    if (!Array.isArray(arr)) {
        return [];
    } 
    if (typeof pageSize !== 'number' || typeof pageNumber !== 'number') {
        return arr;
    }
    if (pageNumber < 1) {
        pageNumber = 1;
    } 
    --pageNumber; // decrements pageNumber to the correct index
    return arr.slice(pageNumber * pageSize, (pageNumber + 1) * pageSize);
}

Example:

const items = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
const pageSize = 3;
const pageNumber = 2;
const page = paginateArray(items, pageSize, pageNumber);
console.log(page); // Output: [4, 5, 6]